Device for automatic control for closing means of regenerative air heaters



M y 1 H. OBERDORFER ET AL 2,982,308-

DEVICE FOR AUTOMATIC CONTROL FOR CLOSING MEANS OF REGENERATIVE AIR HEATERS Filed Nov. 4, 195a INVENTURS: F/ei Mal 2% @m, 1 BYM%WWA4 m A mrney,

DEVICE FOR AUTOMATIC CONTROL FORCLOS: ING MEANS OF REGENERAT IVE AIR HEATERS United at s Patent o Heinz Oberdorfer Alfons Dauber, Zweibruclren,Ger-

many, assignors to Dinglerwerke Aktiengeseilschaft, Zweibrucken, Germany Filed Nov. 4, 1958, Ser. No. 771,902 4 Claims. 01. 137-62418) The present invention relates to a device for the after a change-over of the system of conduits from air to gas or from gas to air,the control of the upward or of the downward strokes is released and further operated in the prescribedsequence from slide to slide by the valves. The invention resides mainly in that the compressed air supply conduit is bifurcated in a double conduit which forms a supply conduit and a return conduit at a changeover cock serving as a control apparatus and which is capable of being, at will, connected to one or to the other of the bifurcated conduit for alternatively supplying compressed air and evacuating the return air, while each of the working cylinders on the air side and on the gas side has two connections and is capable of being connected with the supply and with the evacuating conduits, partly through connecting tubes free of valves and partly through connecting tubes including valves which are controlled in'dependence of the movement of the slides.

The advantage which results from such an arrangement resides in the fact that valves which are to be cn- 2' cylinders which, through the centrally disposed changeover cock 8 (control device), is connected tothe supply conduit 9 supplying the compressed air. cook 10 is disposed beforethe change-over cock 8. The

closing cook 10, when in closed position, is also connected to open air. The change-over cock 8 which is provided with the operating handle 11 is capable of taking one or the other of the positions shown in Figures 1 and 2, re-

spectively. In the position of Figure 1, the compressed air enters the supply conduit 6. At the same time, return air passes through the conduit 7. In the position of Figure 2, however, the conduit 7 becomes the supply conduit and the supply conduit 6 becomes the return conduit.

in both cases, the return air is evacuated in the atmosphere through the evacuating pipe 27. i

Thedouble conduit starting from the change-over cock 8 is disposed verticallybetween the slide rows of air and and gas side, and consists of the two conduits 6, 7 prolonged above the working cylinders and connected, re-

spectively, to the horizontal conduits 6a and 7a.

The connecting conduits 32, 3 3 to the outer cylinders 13, 14 are free of controlmeans. In the connecting conduits to the other cylinders are inserted control valves, such as 16, provided with control levers such as that denoted by the reference 15.

' denoted by the reference 17, in order that the abutments,

such as 18, provided on these rods, form catches for the control levers 15.

For the adjacent inner cylinders 19, 20 pertaining'to the air-side and to the gas side, respectively, connecting conduits 21, 22 areprovided including, respectively, stop cocks 23, 24 in each of which the closure position for the compressed air corresponds also to an open position for-- lever 11, into the position shown in Figure 2. Comtrolled with compressed air can be suppressed so that restriction and a'pressure drop in the conduit, due to the presence of partially open valves, are obviated; on the contrary, in an arrangement .accordingto the invention,

the compressed air can be directly and at full pressure supplied to each of the cylinders. More particularly, the arrangement of the invention is such that-the air heater can be changed over from air to gas or from gas to air By way of example, an'arrangement according to the invention is described hereunder with reference to the drawings, in which:

Figure l is a schematic view that shows the slidearrangement in position for admitting air, and v Figure 2 is a' schematic view similar to Figure l'but which shows the arrangement changed over to gas.

The slides 1 and 2 which, through links, are connected to the pistons in. the working cylinders, represent the slide row associated to the 'airside'. This slide row is continned towards thegas-side including the slides 3, 4 and 5.

pressed air passes through the conduit 7, into the conduit system of theplant. 7 1, associated with the outer cylinder 13 of the air-side,

assumes its closed position. During its downward movement, the piston of the cylinder 13 pushes the return air into the atmosphere, through the conduit 26, the open valve 25, the conduits 6a and 6, and through the outlet pipe27 ofthe change-over cock 8. As the catch 13 provided on the piston rod 17 acts on the control lever vl5 of the valve 16, only when the slide 1 of Figure 2 assumes its closed position (Figure 2), the said valve 16, provided in the conduits 28, 23a, is brought to its open position as soon as slide 1 assumes its closed position. is delivered to cylinder 19 which is the cylinder associated with the slide 2 adjacent to slide 1 whichhas just been moved into its closed position. As the closure movement of the slideZ starts, the return air is evacuated into the atmosphere, through the connecting conduit 21 in which are inserted the open valve 30 and the open stop-cock 23, through the conduit 6 and the evacuating pipe 27 at the change-over cock 8.- As the slide I v 2 assumes its closed position, the valve 31 is positively ,opened, and, compressed air passes through the supply; conduit '7 and enters the next cylinder 20 of thegas side, through the-connecting conduit 22 comprising the Theconnecting conduits. associated witheach-of the cylinders are connectedto one and to theother conduits of the double conduit 6, 7, 6a and 7a; which constitutes i the main conduit andformsa connecting, conduit for all open valve 31 and the cock -24which is'in its open I This positive action, which is performed step by step toward the gas-side and which permits to'obtain' "the open positions of the valves for opening the whole position.

The closing The control valves- 16 are I disposed in the vicinity of the piston rods, such as that As a consequence, the slide By opening of the valve 16, compressed air cross-section of the conduits, goes on until all of the slides assume the positions shown in Figure 2.

The same operations are to be made if the plant, being regulated for gas, is to be changed over for air by bringing the change-over cock 8 from its position of Figure 2 into its position of Figure 1. There is, in this case, a difierence from the above described mode of operation, which consists in that the air-position shown in Figure l is obtained by the stepwise operation from slide to slide, in the reverse direction, that means from the gas-side to the air-side. I

The closure of all of the slides from the air-positio according to Figure 1 presupposes that the position of the cock 23, inserted in the connecting conduit 21, is so selected that the said cock 23 comprises an air release position for evacuating the return air flowing out from cylinder 19, through conduit 21, and that the cock 24 takes a closure position by which compressed air is prevented from entering the cylinder 20, through conduit 22, whereby the automatic stepwise operation from the air-side to the slides 3, 4, of the gas-side is rendered impossible. On the contrary, the closure of all of the slides from the plant in gas-position, as shown in Figure 2, is made possible by the fact that the cock 24, inserted in the connecting conduit, liberates the return air from cylinder 20, and that the cock 23 in the conduit 21 prevents compressed air supply to the cylinder 19, so that the stepwise operation is restricted to the slides 3, 4 and 5 of the gas-side and cannot act on the slides 1 and 2 of the air-side.

What we claim is:

1. In a plant for automatically controlling pressure medium actuated closure means of regenerative air heaters, including a row of adjacent working cylinders and associated closure slides for air and for gas adapted to be operated by said cylinders, and control valves inserted in connecting conduits supplying the said cylinders with said pressure medium, the said control valves controlling the stepwise operation of the slides in a prescribed sequence, a main conduit for said pressure medium, a change-over cock connected to said main conduit and having an outlet tube for communication with the atmosphere, two parallel conduits connected to said change-over cock and to the working cylinders and said control valves having means to operate them in accordance with the movement of the slides.

2. A plant according to claim 1 further comprising in the main conduit connected to the change-over cock a stop cock having an air release aperture leading into the atmosphere when said change-over cock is in its closed position for the pressure medium.

3. A plant according to claim 1 in which the two conduits connected to the change-over cock are vertically disposed and pass between and above the cylinders pertaining to the air side and the cylinders pertaining to the gas side and further comprising a set of transversely disposed distributing conduits to which lead the said vertically disposed conduits, connecting conduits between the distributing conduits and the cylinders.

4. A plant according to claim 3 in which said valve means are comprised in the connecting conduits between the vertical conduits and the adjacent cylinders from air-side and gas-side and comprise stop cocks one of which prevents the passage of pressure medium when in its closed position, while the other is adapted to release air into the atmosphere through the connecting conduits and the change-over cock when it is in its open position.

References Cited in the file of this patent UNITED STATES PATENTS 1,799,113 Miedbrodt Mar. 31, 1931 1,905,065 Scholl Apr. 25, 1933 2,252,800 Daniels Aug. 19, 1941 

